add removeNullAttributes feature

Author: jeremydaly

README.md

@@ -256,6 +256,7 @@ const MyTable = new Table({
 | indexes | `object` | no | Complex type that optionally specifies the name keys of your secondary indexes (see below) |
 | autoExecute | `boolean` | no | Enables automatic execution of the DocumentClient method (default: `true`) |
 | autoParse | `boolean` | no | Enables automatic parsing of returned data when `autoExecute` is `true` (default: `true`) |
+| removeNullAttributes | `boolean` | no | Removes null attributes instead of setting them to `null` (default: `true`) |
 | DocumentClient | `DocumentClient` | * | A valid instance of the AWS [DocumentClient](https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/DynamoDB/DocumentClient.html) |
 
 \* *A Table can be instantiated without a DocumentClient, but most methods require it before execution*

classes/Entity.js

@@ -488,8 +488,9 @@ class Entity {
     const names = {}
     const values = {}
 
+
     // Loop through valid fields and add appropriate action
-    Object.keys(data).forEach(function(field) {
+    Object.keys(data).forEach((field) => {
       const mapping = schema.attributes[field]
 
       // Remove attributes
@@ -507,6 +508,9 @@ class Entity {
           REMOVE.push(`#${attr}`)
           names[`#${attr}`] = attr
         } // end for
+      } else if (this._table._removeNulls === true && (data[field] === null || String(data[field]).trim() === '') && (!mapping.link || mapping.save)) {
+        REMOVE.push(`#${field}`)
+        names[`#${field}`] = field
       } else if (
         !mapping.partitionKey
         && !mapping.sortKey
@@ -781,6 +785,7 @@ class Entity {
           return value !== undefined
             && (mapping.save === undefined || mapping.save === true)
             && (!mapping.link || (mapping.link && mapping.save === true))
+            && (!_table._removeNulls || (_table._removeNulls && value !== null))
             ? Object.assign(acc, {
               [field]: value
             }) : acc

classes/Table.js

@@ -51,6 +51,12 @@ class Table {
   // Gets the current auto execute mode
   get autoParse() { return this._parse }
 
+  // Sets the auto execute mode (default to true)
+  set removeNullAttributes(val) { this._removeNulls = typeof val === 'boolean' ? val : true }
+
+  // Gets the current auto execute mode
+  get removeNullAttributes() { return this._removeNulls }
+
   // Retrieves the document client
   get DocumentClient() { return this._docClient }
 

lib/normalizeData.js

@@ -11,7 +11,7 @@ const { error } = require('./utils')
 
 // Normalize Data
 module.exports = (DocumentClient) => (schema,linked,data,filter=false) => {
-  
+
   // Intialize validate type
   const validateType = validateTypes(DocumentClient)
 

lib/parseTable.js

@@ -22,6 +22,7 @@ module.exports = table => {
     indexes,
     autoExecute,
     autoParse,
+    removeNullAttributes,
     entities,
     DocumentClient,
     ...args // extraneous config
@@ -87,6 +88,7 @@ module.exports = table => {
     },
     autoExecute,
     autoParse,
+    removeNullAttributes,
     _entities: [] // init Entity tracker
   },
   DocumentClient ? { DocumentClient } : {}, // end DocumentClient